Dynamo-electric machine.



D. BALACHOWSKY & P. GAIRE. DYNAMO ELECTRIC MACHINE. APPLIGATION FILED JUNE 16, 1909.

Patented Mar. 30, 1915 [I I w as "3 I i:' I WFIIIIII l a ii I II N DIMITRYBALAcHowsKYmNn PHILIPPEJCAIRE, tor =NEUILLY-SUR-SI I a 8;;FRANCE.

ToaZZ whom, it mag concern: I g 7 Beat known" that we, DrMrrnY BALACHOW- sin? and PHLLIPPEQCAIRE, both residents of. Neuilly-sur-Seine, Seine, France, the former. I a subject of theEmperor ofRu'ssi'a, the'latter acitizen of the Republicof France,.have invented newand useful Improvements; in, DynamorElectric; Machines, which -impro ve-' ments are ifullyI-set =1fo'rthii11 "the follow ng specification. f a

of direct-current electric. 'machines.

tained by compoundfwinding, ThisIhow ever'does'not-give a sufficiently close reg u-V lationl fortall purposes, and "therangc ofregulation :is: undesirably limited.

' The 1 invention consists in the combination,

-.with, the: armature and field of the. machine,

of means controlled by the Shifting of, the neutral line due, toarmature reaction, for

varyingthe strength of the field. Such means-may comprise two, brushes of "like specially designed auxiliary field coil.

In the accompanying drawing, Figure 1 The object a of the present*inventionisto provide means; for i the automatic regulagtiog i all: regulation has heretofore been comm'bnly at- 1 sign bothysitu'ated in :the same zone of comv mutation, saidbrushes beingconnectedto a 'Speciflcationof lettersrfatent.

a generator of the type describe-d', turnin at constant speed in the? direction indicated shows con ventionally'a bipolar generator, to

which the invention isapplied, and Fig, a bipolar generator provided with the invention aszshown in Fig.1,Iand with. meansspeciallyuseful in starting the machine.

, Similar letters of reference indicate cor respondingparts in the; figures.

Referring. to thed-rawings, the armature 10' is mounted. to rotate in the usualmanner I between the poles 11 and121of the field, and.

is. provided with HwfiOIIlIIllltEtO! 13, from which the current generated is taken by brushes k, Z, and delivered through suitable Wire conductors to the terminals (1,1). The

' clud'edbetweenthem-areremoVed fromcthc pole faces and cutfonly a smallrfluxp The sameis true of brushes-Z ancl' Z;

Between the principal brushlof positive s gn, 70,7 and the auxiliary brushof the" same s1gn,'lc", is interposed an ami iliaryyfieldscoil Patented] Tan-30, 1915. Application name 16,1909. seri I i,fand likewise, zbetween :th'eumainn. brush Z;

and theauxiliary brush .Zof negative sign, is interposed an auxiliary field-coil"il The. brushes may be of any suita'blez f'usual typeai,

and mounted in theordinary manner, which 7 a will bewell understood without :detaileddescription. Furthermore the number of-principal' and auxiliary brushes-1: depends... only upon sthe number of pole's' andl the winding; O a

the machine. Assuming that for the 'norr m-al or mean value of currentandvoltage- 0f.

by the arrow in"F-ig.' 1, the neutral' lineisn; atflequaldistanoefrom the two :brushes; of] like polarity, then, as'the current vwhichzmay pass in the. coils i and z' dependsionly on the a valueof the electromotive forcebtween the.

brushes of like polarity,- k and k' for coil 41, and Z- and Z for coil 11, the, electromotivexforceandcurrentdnii andxi is in thistin stance nothing. Assuminghowever that? through: a variation in the resistance thecurrent increases. The neutral .line will ap-.- I

proach the position 0 n An velectromotive force will thereby be created between Z and Z and between is and *lcf thus-causing a current .7

in the coils?) and z"; Thisr current will act to diminish the flux issued from :the poles, the armature reaction helping; if thexvalues of 'Zand z" are properly determined, the flux will decrease and "the: voltage will decrease in the same ratio'that the current'increases,

field-coils sa-re .inthe usualmanner connected as a shunt, at the terminals. Inaddition to thesemain-brushes-k and Z there are placed on the commutator other brushes, k and- Z, brush lat-being in the same zone of commutation asbrush k,-.and brush Z" in the same zone as Z; that is to say, the neutral lineiof the armature isaa substantially hori-' zontal line o-n across the center, of the armature andcommutator, between hand k on one sideand between Z and Z on; the other.- The distancebetween brushesk. and is is small, and theirz position on thecommutator issuch that the armature coils; in-

and the energy resulting, therefore remains constant. If, onthecontrary, thexcurrenh had decreased, the neutral "line" would have moved in the opposite direction, respectively nearer k and Z, the :currentinthe; coils z and i" would'have been .produced in" the opposite direction and would have helped increase the flux in such vmanner as:

to increase the voltage in thezsameratio that the current had decreased The novelty of ourinvention lies'inot merely in the auxiliary field-coils,l,but in the excitation of those coils by at. current from a difference of potential occurring. on-

opposite sides of the neutral line in a zone of: commutation.

The armature being rotated,g current, is

- generated in the coils of the same, and fiows through the brushes is, k, conductors 1a and 15, and coil 71 to the terminal a, and coil 8 to the terminal 6. From the positive terminal a it is taken for use by any suitable conductor. The part of the current shunted I through the field-coil s and returning at the terminal I) completes its circuit through the machine, together with the main return which also enters at the terminal I), through coil i,conductors 16 and 17, and brushes Z, Z.

As above stated, the main coils are mounted shunt with the armature winding. In certain circumstances it may be useful to have a shunt machine working as a series machine, for instance when the circuit of a dynamo is suddenly closed on a very small resistance the machine would not be excited if it were only shunt, but ought to have a strong series excitation; this may also be useful to gradually come back tothe former excitation. For this purpose the following device is employed, the same being shown in Fig. 2. The additional field coils/i, i, are constantly connected to one of the brushes (/1: or Z for instance) the connection to the other corresponding brushmay be cut off or suitable resistance may be thrown in. The line is, however, always directly connected to the end a b of the coils z', i, the resistance being also thrown in between the line and the corresponding additional brush. nor example in Fig. 2 the coil 2' is always connected to the brush is and to the line at a. The other brush m" is connected to a by variable resistance-m. These connections can alto be completely out out.

The operation of the device of Fig. 2 is as follows: When the switches 0 and 0' are opened, the entire current from the armature passes from L and Z through i and the line. The coils'z' are series Wound. When now is and Z are connected to a and Z) by closing the switches, a part of the current of the armature passes by i, the rest going to the line from la and Z through the resistances. As the resistance decreases, that part of the current that passes through 2' decreases until, when the connection is made'di'rectly bev J said auxiliary windings.

tween 7a and a, and between Z and b, the

conditions of Fig. 1 are approximated and the current passing through i depends only i on the value of the electromotive force be tween the brushes in the same zone of com- I 51$ main set, said zones of commutation embracing the neutral points, the field winding being composed of a prevailing shuntwinding and an auxiliarywinding having coils iliary brush of the other set and the negative main brush of one set with the negative auxiliary brush of the other set.

2. In a dynamo electric machine, a field- Winding producing a fie d of opposite poles, an armature intermediate said poles, a commutator, a double set of brushes including which connect respectively the positive a main brush of one set with the positive auxa main set and an auxiliary set, each brush of the auxiliaryset being in the same zone of commutation as one" brush of the mainv set, said zones of commutation embracing the neutral points,the field'winding being composed of a prevailing shunt winding and an auxiliary winding having coils which connect respectively the positive main brush of one set with the positive auxiliary brush of the other set and the negative main brush of one set with the negative auxiliary brush of the other set, and Variable resistances in In testimony whereof specification in the presence of two sub scribing witnesses. a

nnvurn. r BALACHOWSKY. v PHILIPPE CAIRE. -Witnesses: EMILE LEDRET,

DEAN B. Mason.

We have signed this 

